Yamhill County was one of the first “Districts” of Oregon, created July 5, 1843. At that time it encompassed an area between the Willamette River and the Pacific Coast and extending north-south from the Columbia River to the California border. By 1845, when Polk County was created, our county was smaller in size than it is today, but still extended to the Coast. Its size grew in a northerly direction in 1847 and, with minor changes in the years since, has remained at about the current 718 square miles
McMinnville is the county seat of Yamhill County. The governing body of the county is the Board of Commissioners, which is comprised of three paid members, elected at-large.
The Yamhill County Fair is Oregon’s oldest county fair. The first fair in Yamhill County was held on October 7, 1854, in Lafayette. It was sponsored by the Yamhill County Agricultural Society, which formed in 1853.